Arrived dead. All voltages are fine. recapped all the boards. Still no action. There’s no Xtal clock pulse on pin 39 of CPU. Changed Xtal caps…still no action. Checked reset pin 37 and it’s going low on start up then high. Tried a NOS CPU but nothing. It’s got version 1.11 Eprom. Could tge Eprom be corrupted? I checked it on my Gq4x4 and it wasn’t flagged as inoperable, but does that mean anything? Running out of ideas.
As long as there is no clock signal on pin 39, the CPU will not boot.
It is unlikely that the Xtal capacitors have a problem, but I would not say the same about the quartz !
Hi Didier, Thank you. I’ll pop another xtal in and see if I can get the heartbeat back